Article
Multidisciplinary Sciences
Kohsuke Mori, Naoki Hashimoto, Naoto Kamiuchi, Hideto Yoshida, Hisayoshi Kobayashi, Hiromi Yamashita
Summary: Fabrication of high-entropy alloys (HEAs) nanoparticles (NPs) on conventional catalyst supports remains challenging, but the authors demonstrate that titanium dioxide (TiO2) is a promising platform for the low-temperature synthesis of supported CoNiCuRuPd HEA NPs with excellent activity and durability in CO2 hydrogenation.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Virgil Andrei, Robert A. Jagt, Motiar Rahaman, Leonardo Lari, Vlado K. Lazarov, Judith L. MacManus-Driscoll, Robert L. Z. Hoye, Erwin Reisner
Summary: In this study, photocathodes with long-lasting H2 evolution activity were demonstrated by integrating a BiOI light absorber into a robust, oxide-based architecture with a graphite paste conductive encapsulant. Multiple-pixel devices were introduced as an innovative design principle for PEC systems, showing superior photocurrents, onset biases, and stability compared to conventional single-pixel devices.
Article
Energy & Fuels
Xuanxiao Chen, Yan He, Xuemin Cui, Leping Liu
Summary: In this study, a high value-added process using blast furnace slag to prepare catalysts for the hydrogenation of carbon dioxide to methane was proposed. The addition of CeO2 improved the dispersion of Ni particles and enhanced the catalytic performance. This research provides an effective way for carbon dioxide emission reduction and high-value utilization of blast furnace slag.
Article
Chemistry, Multidisciplinary
Thomas A. Rogers, Luis G. Encarnacion-Gomez, Andreas S. Bommarius
Summary: This study presents and validates two alternative methods for estimating the total turnover number (TTN) of a biocatalyst at any desired operating temperature. The first method is a mechanistic approach that calculates TTN from two straightforward isothermal biochemical batch measurements, while the second method relies on non-isothermal continuous experiments and mathematical modeling to determine the intrinsic deactivation parameters of the biocatalyst. Both methods provide accurate estimates of TTN and are more time-efficient and convenient compared to conventional isothermal aging tests.
Article
Metallurgy & Metallurgical Engineering
Yitong Yang, Jingyu Pang, Hongwei Zhang, Aimin Wang, Zhengwang Zhu, Hong Li, Guangquan Tang, Long Zhang, Haifeng Zhang
Summary: In this study, the growth behavior and coarsening kinetics of cuboidal nanoparticles in Ni44Co22Cr22Al6Nb6 MPEA were systematically investigated. The nanoparticles exhibited growth and split behavior in the initial stage of isothermal aging, leading to improved mechanical performance. After long-term isothermal aging, the cuboidal nanoparticles retained superior thermal and mechanical stability. The Ni44Co22Cr22Al6Nb6 MPEA showed higher activation energy and slower coarsening rate constant compared to traditional Ni-based superalloys, indicating sluggish elemental diffusion and enhanced stability.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2023)
Article
Chemistry, Physical
Mengzhi Guo, Hong Meng, Junsu Jin, Jianguo Mi
Summary: A nitrogen-doped carbon-encapsulated Ni3Fe alloy catalyst was fabricated through a tetraethylenepentamine-induced thermal reduction strategy. The 3D porous-sheet structure of the catalyst provides a large specific surface area and more active sites. The nitrogen-doped carbon shells act as protective layers and electron donors for modulating the electronic structure of the active center, leading to enhanced performance in both the oxygen evolution and hydrogen evolution reactions.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Nanoscience & Nanotechnology
Bozhen Wu, Xuejiao Song, Dongchen Zheng, Qianyun Tan, Yong Yao, Fa-Qian Liu
Summary: Inspired by natural wood, a biochar with a highly ordered pore structure and excellent thermal conductivity was prepared as a carrier for organic amines to prepare ideal CO2 adsorbents. The prepared adsorbent showed high adsorption capacity, stable performance, ultrafast adsorption kinetics, and low regeneration heat, making it promising for CO2 capture.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Yu Xie, Jianjun Chen, Xi Wu, Junjie Wen, Ru Zhao, Zonglin Li, Guocai Tian, Qiulin Zhang, Ping Ning, Jiming Hao
Summary: This study investigates the relationship between the active-site structure and CO2 methanation mechanism over Ni-based catalysts. The results show that Ni/CeO2 nanorods with enriched frustrated Lewis pair (FLP) structures exhibit higher CO2 conversion and methane selectivity at low temperatures.
Article
Chemistry, Inorganic & Nuclear
Quanhui Hou, Jiaqi Zhang, Zhu'An Zheng, Xinglin Yang, Zhao Ding
Summary: The Ni3Fe/BC nanocatalysts prepared in this study can effectively improve the hydrogen storage performance of MgH2. The composite exhibits a lower onset temperature of hydrogen release, lower hydrogen absorption temperature, and higher hydrogen absorption and desorption rates compared to pure MgH2. It also demonstrates good cycling stability.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Farnoosh Goodarzi, Mikkel Kock, Jerrik Mielby, Soren Kegnaes
Summary: This work demonstrates the high activity and selectivity of Ru nanoparticles supported on high surface area nano MgO as a catalyst for CO2 methanation. The catalyst showed stable performance with the highest conversion and site time yield. In comparison, the Ni-based catalyst exhibited lower conversion and selectivity. Additionally, the Ru on high surface area MgO catalyst showed promising activity at low temperature.
JOURNAL OF CO2 UTILIZATION
(2023)
Article
Materials Science, Multidisciplinary
Qiancheng Zhou, Xiangnong Tang, Shunhang Qiu, Liyuan Wang, Lina Hao, Ying Yu
Summary: High-selective and stable electrocatalysts are prepared using a combination of chemical oxidation and electrodeposition method. The CuIn alloy nanowires achieve high selectivity and stability for CO2 reduction to CO, and the alloy surface plays a crucial role in the modulation of *COOH intermediate bonding and inhibition of *CO dimerization. This work provides insights into the preparation of stable electrocatalysts for CO2 reduction and understanding metal surface evolution under electrochemical environment.
MATERIALS TODAY PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Bogdan Jurca, Lu Peng, Ana Primo, Alvaro Gordillo, Amarajothi Dhakshinamoorthy, Vasile Parvulescu, Hermenegildo Garcia
Summary: This study investigates the influence of metallic and non-metallic elements on the catalytic activity of Co-Fe@C catalysts. Pd enhances CO2 conversion and CH4 selectivity, while Ce reduces CO selectivity. The presence of Ca remarkably increases CO2 conversion and CH4 selectivity, while sulfur acts as a strong poison. The combination of sulfur and alkali metals maintains selectivity and increases conversion.
Article
Chemistry, Physical
Zouhair Boukha, Alejandro Bermejo-Lopez, Benat Pereda-Ayo, Jose A. Gonzalez-Marcos, Juan R. Gonzalez-Velasco
Summary: The performance of nickel catalyst supported on lanthana-modified hydroxyapatite (HAP) in CO2 methanation was investigated, with La addition improving the dispersion and reducibility of Ni particles, increasing the amounts of basic sites and their thermal stability, leading to enhanced catalytic activity.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Energy & Fuels
Hengyu Wan, Yan He, Qiaoqiao Su, Leping Liu, Xuemin Cui
Summary: Geopolymers as catalyst supports show promising catalytic performance for CO2 methanation. Catalysts prepared using KOH-activated chemically synthesized slag and ground granulated blast furnace slag demonstrate higher CO2 conversion and CH4 selectivity.
Article
Chemistry, Physical
Jiachen Gao, Zishan Han, Xinyu Wang, Lu Wang, Yong Guo, Changjun Cui, Daliang Han, Linjie Zhi, Quan-Hong Yang, Zhe Weng
Summary: In this study, a self-limited reconstruction strategy was proposed to achieve highly dispersed copper nanoparticles with robust structural stability during electrocatalysis. By selecting copper-based complex precursors with flexible ligands and strong metal-ligand interaction, the oxidation and agglomeration of copper nanoparticles were effectively prevented, resulting in excellent performance.
Article
Chemistry, Applied
Vasyl Marchuk, Xiaohui Huang, Vadim Murzin, Jan-Dierk Grunwaldt, Dmitry E. Doronkin
Summary: This study investigates the reaction mechanism and performance variation of bifunctional Fe-Pt ammonia slip catalysts, revealing the significant influence of active metal state on reaction conditions and catalyst bed layout. The study also examines the impact of non-equilibrium phenomena on catalytic performance.
TOPICS IN CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Meng Yang, Jiafeng Yu, Anna Zimina, Bidyut Bikash Sarma, Lakshmi Pandit, Jan-Dierk Grunwaldt, Ling Zhang, Hengyong Xu, Jian Sun
Summary: Atomically dispersed Zn on ZrO2 support in Cu-based catalysts was achieved via double-nozzle flame spray pyrolysis method, showing superiority in methanol selectivity and yield compared to Cu-ZnO interface and isolated ZnO nanoparticles. Operando X-ray absorption spectroscopy revealed that the atomically dispersed Zn species were induced during the reaction due to the strengthened Zn-Zr interaction. This work provides insight into the rational design of unique Zn species and offers a new perspective for exploring complex interactions in multi-component catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Linda Klag, Thomas L. L. Sheppard, Jan-Dierk Grunwaldt
Summary: The selective oxidation of propylene and isobutene plays a central role in the chemical industry, with bismuth molybdate based multicomponent systems being commonly used as catalysts. Previous research has provided a detailed understanding of the mechanism using simplified model catalysts, but now new concepts and characterization methods allow for the study of more complex multicomponent catalysts. The importance of integral and spatially-resolved approaches is discussed, highlighting the need for interdisciplinary research.
Article
Chemistry, Inorganic & Nuclear
Gereon Behrendt, Nils Prinz, Anna Wolf, Lorena Baumgarten, Abhijeet Gaur, Jan-Dierk Grunwaldt, Mirijam Zobel, Malte Behrens, Sebastian Mangelsen
Summary: The phase width of copper hydroxycarbonate malachite upon substitution with magnesium was studied, and crystalline hydroxycarbonate samples with up to 37% magnesium were obtained. The study revealed that samples with up to 18% magnesium were phase-pure magnesian malachites, but the magnesium content can be increased beyond this threshold when mcguinnessite is accepted as a side phase. The samples were found to be promising candidates for the preparation of Cu/MgO catalysts.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Bidyut Bikash Sarma, Jelena Jelic, Dominik Neukum, Dmitry E. Doronkin, Xiaohui Huang, Felix Studt, Jan-Dierk Grunwaldt
Summary: The structural changes of CeO2-supported single-atom catalysts (SACs) under reducing and oxidizing reaction atmospheres were studied. It was found that the changes in CO vibrational frequencies can indicate the oxidation state of the metals. Pt2+ and Pd2+ are more prone to cluster formation, while Rh3+ and Ru4+ remain as single sites.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Kevin Keller, Patrick Lott, Steffen Tischer, Maria Casapu, Jan-Dierk Grunwaldt, Olaf Deutschmann
Summary: The presence of water vapor during the oxidation of methane over PdO-based catalysts inhibits the reaction and deactivates the catalyst. This study investigates the role of different support materials at various water concentrations in the reaction gas mixture. Compared to PdO/Al2O3, SnO2 and ZrO2 show enhanced catalytic activity and stability in the presence of 12% H2O, with CH4 conversion dropping by only 68%. The interaction between Pd species and catalyst support is characterized through thermogravimetric analysis, temperature-programmed reduction experiments, and TEM measurements, and a kinetic scheme is derived from the experimental data.
Article
Chemistry, Physical
Akash Bhimrao Shirsath, Manas Mokashi, Patrick Lott, Heinz Muller, Reihaneh Pashminehazar, Thomas Sheppard, Steffen Tischer, Lubow Maier, Jan-Dierk Grunwaldt, Olaf Deutschmann
Summary: Methane pyrolysis is an attractive process for hydrogen production and carbon sequestration. Understanding the formation of soot particles in methane pyrolysis reactors is important for scaling up the technology, requiring appropriate soot growth models. A numerical simulation is conducted, coupling a mono disperse model, plug flow reactor model, and reaction mechanisms to study the chemical conversion of methane, formation of C-C coupling products and polycyclic aromatic hydrocarbons, and growth of soot particles. The soot growth model considers the effective structure of aggregates and predicts soot mass, particle number, area, volume concentration, and size distribution. Experimental characterization of soot samples is carried out using Raman spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS) for comparison.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Correction
Chemistry, Physical
Bidyut Bikash Sarma, Jelena Jelic, Dominik Neukum, Dmitry E. Doronkin, Xiaohui Huang, Sarah Bernart, Felix Studt, Jan-Dierk Grunwaldt
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Agustin Salcedo, Deniz Zengel, Florian Maurer, Maria Casapu, Jan-Dierk Grunwaldt, Carine Michel, David Loffreda
Summary: Density functional theory (DFT) is used to simulate the anharmonic infrared spectrum of adsorbed CO to study the nature of Pd nanoparticles supported on ceria. Realistic models inspired by ab initio molecular dynamics are explored to determine how various factors affect the simulated spectra, and the results are compared with in-situ DRIFTS experiments. Truncated octahedral NPs with an acute Pd-ceria angle are found to accurately describe the active sites in the real catalyst.
Article
Chemistry, Physical
Dan Zhao, Mingbin Gao, Xinxin Tian, Dmitry E. Doronkin, Shanlei Han, Jan-Dierk Grunwaldt, Uwe Rodemerck, David Linke, Mao Ye, Guiyuan Jiang, Haijun Jiao, Evgenii V. Kondratenko
Summary: This study investigated the effects of diffusion on the performance of ZnOx catalysts in propane and isobutane dehydrogenation reactions. Molecular dynamics simulations showed that mass transport limitations do not play a significant role in the PDH reaction, but do affect the iBDH reaction. X-ray absorption spectroscopy revealed that the nature of active ZnOx sites depends on the support material.
Article
Engineering, Environmental
Akash Bhimrao Shirsath, Mariam L. Schulte, Bjarne Kreitz, Steffen Tischer, Jan-Dierk Grunwaldt, Olaf Deutschmann
Summary: CO2 methanation via the Sabatier reaction using green H2 is a promising technique for achieving carbon-neutral energy balance. Nickel-based catalysts, due to their low cost and high activity, are commonly used. This study combined numerical simulations with microkinetics and mass transport limitations to compare the performance of two catalysts at different temperatures. Incorporating spectroscopy studies, the importance of integrating modeling with experiments was demonstrated to improve accuracy in multiscale models.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Linda Klag, Abhijeet Gaur, Matthias Stehle, Sebastian Weber, Thomas L. Sheppard, Jan-Dierk Grunwaldt
Summary: This study systematically investigated the activity and selectivity of Bi-Mo-Co-Fe oxide catalysts in selective oxidation of isobutene. The results showed that the activity and selectivity of the catalysts depend on the variety and interaction of metal oxide phases, and the reducibility of Fe3+ is crucial for catalytic activity.
Article
Nanoscience & Nanotechnology
Chiara Mazzariol, Francesca Tajoli, Alexander E. Sedykh, Paolo Dolcet, Jan-Dierk Grunwaldt, Klaus Muller-Buschbaum, Silvia Gross
Summary: Controlling the properties of inorganic materials, such as size, shape, and functional properties, is a main focus in material development. Confined reactions within nanoreactors have shown to have advantages over traditional methods in terms of control and uniformity. A study on calcium molybdate nanophosphors found that confinement in a miniemulsion approach resulted in more uniform size, shape, and doping effectiveness, leading to improved photoluminescence properties.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Physical
Vasyl Marchuk, Xiaohui Huang, Jan-Dierk Grunwaldt, Dmitry E. Doronkin
Summary: The influence of Pt particle size and structure on the catalytic performance in selective ammonia oxidation for emission control applications is poorly understood. In this study, operando XAS was used to complement traditional laboratory tests to determine the factors governing activity and selectivity in Pt catalysts with different particle sizes. It was found that the increase in activity with particle size was mainly due to the presence of favorable Pt ensembles on the surface. Spectroscopic data revealed different reaction mechanisms for particles above and below a size threshold of about 2 nm. The evolution of these mechanisms correlated with catalyst activity and selectivity change.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Meng Yang, Jiafeng Yu, Anna Zimina, Bidyut Bikash Sarma, Jan-Dierk Grunwaldt, Habib Zada, Linkai Wang, Jian Sun
Summary: Converting CO2 into methanol is of great significance in the sustainable methanol economy. In this study, single-site Zr species in an amorphous SiO2 matrix were created by enhancing the Zr-Si interaction in Cu/ZrO2-SiO2 catalysts. It was found that CO2 preferentially adsorbs on the interface of Cu and single-site Zr, rather than on ZrO2 nanoparticles. Methanol synthesis was verified to occur on single-dispersed Zr sites, while the ordinary formate pathway occurred on ZrO2 nanoparticles. This work opens up new possibilities for understanding the role of atomically dispersed oxides in catalysis science.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)